Give players a locked door with a key in the keyhole – but on the...

Give players a locked door with a key in the keyhole – but on the other side. In order to get the key and unlock the door, players must slide something flat, like a piece of paper or a mat, under the door so it sits below the doorknob. Then they must poke something into their side of the keyhole to push the key out, so it lands on the flat object. They can then retrieve the key by carefully pulling the flat object back to their side of the door. [Note: With a puzzle like this, you must have a backup solution prepared in case the players push the key out without something there to catch it. Unlike a video game, where players can recognize that they missed a step and go back to try again, in real life, once the key is on the floor in the next room, the first solution will never be possible again.]